Subcutaneous (SC) administration of therapeutic ketamine has been explored as an alternative to intravenous (IV) and other routes of administration for managing mental health, depression, and other conditions. While research is limited, some studies have demonstrated this method’s potential benefits and concerns. This ROA is hardly ever mentioned in clinical practice.
Benefits:
- Less-invasive and convenient: SC administration is less invasive than IV administration and can be more suitable for patients, potentially improving treatment adherence (Fisher et al., 2019).
- Steady drug release: SC administration allows for a slower and more consistent release of ketamine into the bloodstream, which may result in more stable plasma concentrations and prolonged therapeutic effects (Carr et al., 2004).
- Bypassing first-pass metabolism: SC administration, like IV and IM administration, bypasses first-pass metabolism by the liver, resulting in higher bioavailability than oral administration (Niesters et al., 2012).
Concerns:
- Pain and irritation at the injection site: SC administration can cause local pain, irritation, or inflammation at the injection site, which may be uncomfortable for patients (Fisher et al., 2019). This concern should be less for SC vs. IM injections.
- Dosing: Optimal dosing for SC ketamine has yet to be established, and more research is needed to determine the most effective and safe dosing regimens for various indications.
- Limited research: There is little research on the efficacy, safety, and bioavailability of SC ketamine administration, particularly for depression. More studies are needed to compare this method to other administration routes and establish its clinical utility.
Subcutaneous (subQ) injection involves injecting ketamine into the tissue layer between the skin and muscle.
Pros of subQ ketamine:
- Less invasive than IV administration [1]
- Faster onset than oral routes [2]
- Bypasses first-pass metabolism [3]
- Lower risk of complications than IV [1]
Cons of subQ vs other routes:
- Slower absorption than IM injections [4]
- Shorter effects than IV infusions [5]
- Repeated injections can be painful [1]
- Risk of injection site reactions [6]
- Less evidence on efficacy than IV ketamine [1]
Overall, subQ ketamine is an alternative to IV and IM with simpler administration but possibly less intense effects. More research is needed comparing the efficacy of subQ administration long-term to other routes.
In summary, SC administration of therapeutic ketamine may offer benefits such as non-invasive and convenient drug delivery, steady drug release, and bypassing first-pass metabolism. However, concerns include pain and irritation at the injection site, the need for further research on optimal dosing, and limited research on efficacy and safety.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6048904/
[2] https://www.ncbi.nlm.nih.gov/books/NBK459141/
[3] https://www.tandfonline.com/doi/full/10.1080/07853890.2019.1590661
[4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4605275/
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6139733/
[6] https://www.psychiatrist.com/JCP/ketamine/